Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02425519 2003-05-02
Transportable Part Rack
BACKGR(?UND OF THE INVENTION
The present invention relates to racks for the transport of tliin wall parts
in general,
and more particularly to racks which have the capacity to be loaded and
unloaded at
the top and sides.
1
CA 02425519 2003-04-07
WO 02/069754 PCT/US02/06681
Many sheet metal stampings, plastic panels, and composite carbon fiber panels
go into
the construction of an automobile. In particular, exterior body panels are
often formed
of thin wall parts. The parts are fabricated, for example, in stamping mills,
and are then
transported to assembly lines where the panels are assembled and painted.
Because
many of these stamped parts are visible to the customer, it is imperative that
they be free
of scratches, dings, or distortions. At the same time, for efficient transport
and assembly
it is desirable that these parts be readily and conveniently accessible, while
also being
protected from contact with exterior objects.or with other adjacent parts.
U. S. Patent No. 4,976,092 discloses a rack having a steel frame open to the
top and
sides, and having a horizontal plywood board to which a series of parallel
plastic leaves
are connected by living hinges which are screwed in place. The plastic leaves
are
formed as single sheet thermoformed thermoplastic parts which have projecting
edge
portions which allow the edges of adjacent leaves to nest. This rack receives
individual
metal parts between pairs of plastic leaves. The rack is loaded with parts at
the place of
manufacture, then transported on a forklif3 vehicle, for loading and transport
to
eventually reach its final destination where the metal parts are removed.
Although such
a rack provides advantageous clearance for side loading, it provides certain
deficiencies.
Because the leaves are hinged directly to the plywood board, they have a
tendency to
return to an initial orientation, rather than remaining where positioned. In
addition, the
nesting edge portions can cause the adjacent leaves to lock together to
prevent multiple
leaves from being flipped at once between loading and transport positions.
Moreover,
as the plastic leaves must be replaced from time to time to reconfigure the
rack for new
parts, the removal and reattachment of the leaves to the plywood board is
laborious and
time-consuming, and costly in terms of additional fasteners required.
What is needed is a side or top loading part rack which is rapidly assembled,
easily
operated, easily maintained and which avoids locking or interfereince of
adjacent leaves
when being turned in groups.
2
CA 02425519 2006-01-12
SUMMARY OF THE INVENTION
A rack for the transport of thin wall parts such as automotive body panel
stampings
has a steel frame with two parallel channels positioned on either side of a
planar floor
member. Each channel has a series of parallel slots which receive tabs
extending
downwardly from parallel plastic leaves. The leaves are restricted from
removal from
the rack by rods which extend through the frame beneath the channels and
through
rod openings in the tabs. The plastic leaves are of two types having side
structures
which do not nest. Because the leaves are not hinged to the floor member, they
will
stay in either position due to gravity. The non-nesting leaf side structures
permit a
plurality of leaves to be flipped from one position to the other
simultaneously.
In accordance with one aspect of the invention, there is provided a rack
assembly for
supporting a plurality of workpieces. The rack assembly includes a rigid frame
having
a top wall having portions defining a plurality of sidewardly extending slots,
the slots
being spaced parallel to one another in a front to back direction. The rack
assembly
further includes a plurality of upwardly extending panels, wherein each panel
has at
least one downwardly extending tab which extends through one of the frame
slots.
Portions of each panel tab define a rod opening. The rack further includes a
first rod
extending from front to back through a tab of each of the panels, the rod
being
positioned beneath the frame top wall, wherein the panels are restricted
against
upward removal from the frame by engagement with the first rod and are free to
pivot
within the slots between a first position spaced from an adjoining panel to
define a
loading opening, and a second position in contact with the adjoining panel.
At least one of the panels may have above each tab, a center rib which
projects
rearwardly, and two side ribs which project frontwardly, one on each side of
the
center rib. The lower edges of the ribs may be positioned at approximately the
same
level as a lower margin of the panel adjacent to the tabs and each panel may
be
movable between two positions of repose. In the first position, the panels may
be
inclined toward a rear of the rack, and in the second position, each panel may
be
rotated from approximately 10 to 60 from the first position, into a position
in which
the tabs are inclined toward a front of the rack. In the first position,
3
CA 02425519 2006-01-12
the center rib may be close to the top wall of at least one channel, while in
the second
position, the side ribs may be close to the top wall of the channel.
The panels may be free to pivot in at least two directions.
The frame may include square and rectangular metal tubing that is operable to
provide
forklift entry openings. The forklift entry openings may be four-way forklift
entry
openings.
The frame may include a plurality of front corner posts affixed to a frame
base and
extending upwardly from the frame base, at least one front crossbar extending
laterally between the front corner posts, at least one front horizontal member
extending rearwardly from the front cross bar, and at least one angled front
plate
affixed to the front crossbar and to the front horizontal member.
Inclined ramps may be affixed to the front corner posts.
The frame top wall may include at least one channel having the sidewardly
extending
slots operable to receive the panel tabs and to restrict upward panel removal
when the
first rod is inserted into the rod opening of each panel.
In accordance with another aspect of the invention, there is provided a rack
assembly
for supporting at least one thin wall part. The rack assembly includes a frame
having
at least one channel including a plurality of sidewardly extending slots, the
slots being
spaced substantially parallel to one another in a front to back direction, at
least one
upwardly extending panel, wherein the panel has at least one downwardly
extending
tab extending through one of the slots, portions of the panel tab defining at
least one
rod opening, and at least one rod extending from front to back through the rod
opening, the rod being positioned below an upper surface of the channel. The
panels
are free to pivot within the slots between a first position spaced from an
adjoining
panel to define a loading opening, and a second position in contact with the
adjoining
panel.
3a
CA 02425519 2006-01-12
In accordance with another aspect of the invention, there is provided a rack
assembly
for supporting parts. The rack assembly includes a frame having at least one
channel
including a plurality of sidewardly extending slots, the slots being spaced
substantially parallel to one another in a front to back direction, and at
least one
upwardly extending first leaf of a first leaf type, wherein the first leaf has
at least one
downwardly extending tab extending through one of the slots, portions of the
leaf tab
defining at least one rod opening, and wherein the first leaf has frontwardly
projecting
side margins. The rack assembly further includes at least one upwardly
extending
second leaf of a second leaf type, wherein the leaf has at least one
downwardly
extending tab extending through one of the slots, portions of the leaf tab
defining at
least one rod opening, and wherein the second leaf has rearwardly projecting
side
margins that, in connection with the frontwardly projecting side margins of
the first
leaf, prevent the first and second leaves from interlocking. The rack assembly
further
includes at least one rod extending from front to back through the rod
opening, the rod
being positioned below an upper surface of the channel. The first and second
leaves
are free to pivot within the slots between a first position spaced from an
adjoining
panel to define a loading opening, and a second position in contact with the
adjoining
panel without interlocking.
The present invention may provide a rack for metal stampings having a
plurality of
plastic leaves which are readily removed and replaced. Multiple plastic leaves
may be
pivoted simultaneously without interference between each other. Individual
plastic
leaves may remain where positioned and do not have a tendency to return to an
initial
position. A hinged connection between the plastic leaves and the rack may be
eliminated
Further features and advantages of the invention will be apparent from the
following
detailed description when taken in conjunction with the accompanying drawings.
3b
CA 02425519 2003-04-07
WO 02/069754 PCT/US02/06681
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. I is an exploded isometric view of the rack of this invention.
FIG. 2 is a cross-sectional view of the rack of FIG. 1, a first leaf being
partially broken
away to reveal a second leaf having different side structure.
FIG. 3 is a cross-sectional view of the rack of FIG. 2 taken along section
line 3-3.
FIG. 4 is a fragmentary cross-sectional view of a leaf of the rack of FIG.'2
shown in
relation to a frame channel illustrated in phantom view.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring more particularly to FIGS. 1-4, wherein like numbers refer to
similar parts, a
rack 20 is shown in FIG. 1. The rack 20 has a steel frame 22 which has two
parallel
channels 24 positioned on either side of a planar floor member 26. Each
channel has a
series of parallel slots 28 which receive tabs 30 which extend downwardly from
plastic
leaves 32. The leaves 32 are restricted from removal from the frame 22 by rods
34
which extend through rod openings 36 in the tabs 30.
The frame 22 has a base structure 38 comprised of square and rectangular metal
tubing
44 welded together to provide four way entry openings 40 adapted to receive
the
protruding tines of a forklift vehicle. Four comer posts 42 extend upwardly
from the
frame base structure 38. The height of the corner posts 42 is determined by
the size of
the parts to be accommodated by the rack 20, but will generally be between 12
and 100
inches tall. Inclined ramps 46 are fixed to the front corner posts. The ramps
46 support
the inclined leaves 32 when they are loaded with sheet metal or other thin
wall parts 48.
The leaves are also supported by two angled front plates 50 which are fixed to
a front
crossbar 52, a front horizontal member 54 which extends rearwardly from the
front
crossbar 52, and a front bar 56 which extends upwardly from the base structure
38
4
CA 02425519 2003-04-07
WO 02/069754 PCT/US02/06681
rearward of the horizontal member 54. This front structure serves to maintain
the
parallelism of the panels during shipment, and the particular arrangement of
ramps,
angled front plates, or bars will vary depending on the geometry of a
particular part to
be transported.
The channels 24 may be formed of 1/8 to 1/4 inch thick sheet. As shown in FIG.
1, the
channels 24 are fixed to the base structure 38 of the frame 22. As shown in
FIG. 4, each
channel has a top wall 58 which has portions defining an array of parallel
slots 28. The
two channels 24 are positioned such that the slots of one channel are aligned
with the
slots of the other. The channel top wall 58 is spaced above the base structure
38 by two
parallel channel side walls 60 which have outwardly extending flanges 62 which
are
fixed to the base structure 38 such as by welding. Each slot is about five
inches wide,
and the slots are separated from each other on about 2.5 inch centers.
However, the
spacing or index of the slots may range from I to 5 inches. Each slot is
approximately
three times the thickness of the plastic at the tab, thus for a 1/8 inch thick
tab as
illustrated, the slot is about 3/8 inch wide.
The floor member 26 extends between the two channels 24 and has a top surface
which
is at approximately the same level as the top wal158 of the channels. The
floor member
26 may be composed of two strips 64 of three-quarter inch plywood which extend
in
the front to back direction and which are fastened to the base structure 38,
and a single
sheet 66 of one-half inch plywood which is fastened to the strips.
The two rods 34 may be one-half inch diameter solid steel rods which taper to
3/16
inches in diameter at one-half inch long tapered ends 68. The front beam 70
and the rear
beam 72 of the base structure 38 are provided with oblong holes 74 through
which the
rods 34 are inserted within the channels 24. Flanges 76 extend downwardly at
the front
and rear of the channels 24, as shown in FIG. 2, and have circular or oblong
slots routed
or punched therein through which the rods 34 extend. In addition, a downwardly
5
CA 02425519 2003-05-02
extending plate with a similar sized slot in is welded extending downwardly
from the
channel top walls 58 at a position approxitmtely centered between the front
and the
rear of each channel 24. When received withiai the slots in the flanges 76 and
the
center plates, the rods 34, which may be about 86 inches long, ai-e restrained
from
excessive bending. Once the rods are positioned to extend through the openings
in the
leaf tabs 30, cotter pins 77 are inserted I:hroug x;1/1 6 Ãncli diaineter
holes in the ends of
the rods to restrain the escape of the rods frorn ttic lrame. It should be
noted that the
rods may also be fabricated from nori round parts, and f'rom tubular parts.
Each leaf or panel 32, which may be substantially planar, has two downwardly
extending tabs 30, as best sliown in FI(1. 4, which are received witilin a
pair of slots
28 in the opposed channels. The panels preferably include leaves, sheets,
partitions, or
other substantially planar structures operable to separate the parts supported
by the
rack. Each leaf 32 is configured with customized dunnage structure 78. The
dunnage
structure 78 may be an arrangemc,nt of protrusions aild recesses configured to
engage
and retain a particular metal part 48 laetween the leaves 32. F'or example,
semicircular
shells 80 may have slots routed in them to retain the lower edges of the sheet
metal
parts 48. In any event, the dunnage structure 78 may vary depending upon the
type of
part which is intended to be conveyed within the rack 20.
When the leaves 32 are formed as single sheet thennoformed parts, every
projection
on one surface has a corresponding recess ori the opposed surface. In the
prior art
racks, this relationship between adjacent leaves resulted in nesting
engagement
between leaves in the course of pivoting a leaf' f rnm a loaded to an unloaded
position.
When the leaves nested generally at the position perpendicular to the floor -
adjacent leaves vvould become locked together and would pivot no further.
Hence, to
avoid this nesting, it became necessary to pivot ihe leaves one by one. The
rack 20 of
this invention eliminates entirely this tendency to lock and perrnits
simultaneous
pivoting of groups of leaves. ]'Jesting is eliminated by providing
nonidentical molded
leaves 32: a first leaf 82 which has side niargins 83 which project
frontwardly from a
flange around the dunnage structure, and a second leaf 84 which has side
margins 86
which project rearwardly from
6
CA 02425519 2003-04-07
WO 02/069754 PCT/US02/06681
a flange around the dunnage structure. The dunnage structure is substantially
the same
on both the first leaves 82 and the second leaves 84. The leaves are
interspersed on the
frame altemating between a first leaf 82 and a second leaf 84. As shown in
FIG. 3, the
result of this arrangement is that the frontwardly protruding side margins of
each first
leaf 82 will engage against the rearwardly protruding side margins of a
preceding
second leaf 84. Moreover, the flanges from which the side margins protrude
will
engage against each other without nesting, to permit unhindered sliding
movement
between adjacent side margins as the leaves are pivoted in groups from one
working
position to the other.
As shown in FIG. 4, each leaf has three ribs above each tab, which help to
stiffen the
leaf in the vicinity of the tab, to carry loads away from the tab, and to
support the leaves
at a desired repose angle in both the loaded and unloaded positions. A center
rib 88
projects rearwardly, while two side ribs 90 project frontwardly, one on each
side of the
center rib. The lower edges of the ribs 88, 90 are positioned at approximately
the same
level as the lower margin 94 of the leaf adjacent to the tabs 30. The lower
margin 94 of
each leaf is generally supported on the top surface 92 of the floor member 26.
As shown in FIG. 3, the leaves 32 are each movable between two positions of
repose.
In a first unloaded position, the leaves are inclined toward the rear of the
rack 20, and
toward a brace assembly 96 mounted to a rear cross bar 98 which extends
between the
rear comer posts 42. In the,unloaded position, each leaf is inclined from the
horizontal
plane of the top walls 58 of the channels 24. The second, loaded, position is
rotated
from approximately 10' to 60 from the first position, into a position in
which the tabs
are inclined slightly toward the front of the rack. The amount of inclination
will vary
depending on the transported part. In the first unloaded position, the center
rib 88 will
25 generally be close to or engaging the top wall 58 of the channels 24, while
in the second
loaded position, the side ribs 90 will generally be close to or engaging the
top wall of
the channels.
7
CA 02425519 2003-05-02
The rack 20 will typically be used in a manufKtcturing facility in proximity
to a source
of formed sheet metal parts 48. In its initial setup, all but the first leaves
32 are
pivoted toward the rear of the rack, in the unloacled position. The first leaf
32 is
pivoted toward the front of the rack in the 8oade:.d positiom The first part
48 is
positioned inclined against the first leaf 32, with the lower edge of the part
48 being
restrained by the semicircutar shells 80. The second leaf 32 is then pivoted
from the
unloaded to the loaded position to overlie the first leaf and to surround the
part 48.
The edge structure and other protrusioris of' the duiviage structure 78
protect the part
48 and prevent its contact with other parts. These steps are repeated until
each leaf 32
is loaded with a part 48. Then, the brace assenably 96 is pivoted toward the
front of
the rack to restrain all the leaves in the loaded position.
As shown in FIG. l, the brace assembly 96 has two upwardly extending members
100
connected by a cross member 102. "1"he lower ends of the members 1.00 are
mounted
by pins to brackets 104 which project fi-ontwardly fiom the rear crossbar 98.
One of
the upwardly extending members 1{}() has a 5pring-loaded pin is extendable
into a pin
hole in one of the brackets 104 and which retains the brace assembly in a
nonengaged
position during loading of the parts. A toothed cam 106 extends frontwardly
from the
rear crossbar 98 alongside one of the upwardly extending meinbers 100. Another
spring-loaded pin 108 is fixed to an upwardly extending member 100, and acts
as a
ratchet against the toothed cam 106 to allow the brace assembly to be pressed
down to
engage the loaded leaves. During shipment the parts nlay shift or cornpress,
which
could allow a front to back movement of' the parts. The weight of the cross
member
102 can automatically cause the brace assembly 96 to ratchet into tighter
engagement
to take up any looseness.
It is understood that the invention is not limited to the particular
construction and
arrangement of parts herein illustrated and described, but embraces all such
modified
f orms thereof as come within the scope of the t'ollowing claims.
8
